Lightning arrester



s. M. WEISBERG 2,777,096

LIGHTNING ARRESTER Filed July 24. 1953 Jinnw A? H mm ATTORNEY UnitedStates Patent LIGHTNING ARRES'I'ER Sidney Mortimer Weisberg, Maplewood,N. 1., assignor to Allied Electric Products, Inc., 'Irvington, N. J., acorporation of New Jersey Application July 24, 1953, Serial No. 370,128

Claims. (Cl. 317-69) The invention herein disclosed relates to lightningarresters for television sets.

Objects of the invention are to provide a capable, ellicient lightningarrester, adaptable to the different kinds of leadin wires, either theflat tape or the widely spaced open-twin wiring used with televisionsets, which will make good contact and good grounding connection forboth kinds of wiring and which will be small in size, light weight andlow cost construction and adapted for mounting to suit differentinstallations; for instance, to be supported on the leadin wires, to befastened on to a wall or to be mounted on a ground pipe or the like.

A feature of the invention resides in the provision of a pair offlat-surfaced spark gap members each of which is symmetricallypositioned with respect to the longitudinal axis of an elongatedgrounding member. Each spark gap member has an end portion which ispositioned in proximity to and spaced from the grounding member, therebyproviding a spark gap to the grounding member. The fiat surfaces of thespark gap member are coplanar with respect to a plane normal to thelongitudinal axis of the grounding member. An annular leakage member inthe form of a high-resistance carbon washer surrounds the groundingmember and has a circular flat surface of which symmetrically disposedportions are in simultaneous electrically conductive engagement with thecoplanar surfaces of both grounding members. Fastening means such as anut and washer are threaded on the grounding member and connect thecarbon washer to the grounding member while holding the carbon washerpressed into engagement with the two spark gap members. The singlecarbon washer thus serves as two resistors, the arrester being providedwith terminals which are arranged to con nect both conductors of abalanced two-wire transmission line symmetrically to ground throughdifferent portions of the carbon washer for draining off electrostaticpotentials, each portion being individually shunted by a spark gap forgrounding high voltage surges or the like on the transmission line.

The terminals embody special features which permit a wire disposed ineither of two parallel grooves to be mechanically and electricallyengaged by an H-shaped terminal plate. Advantageously, an arcuate row ofinsulation piercing contact points may be arranged on one of the legs ofthe H-shaped terminal plate for piercing the insulation of an insulatedwire and establishing positive electrical contact with a stranded wireenclosed within the insulation.

Special objects of the invention are to provide firm, positive combinedelectrical and mechanical connection with the leadin wires withouttearing, cutting or otherwise injuring either the wires or, ifinsulated, the insulation protecting the wires.

Other desirable objects attained by the invention and the novel featuresthrough which the purposes of the invention are accomplished are setforth and will appear in the course of the following specification.

The drawing accompanying and forming part of the Patented Jan. 8, 1957specification illustrates a present commercial embodiment of theinvention but the specific structure may be modified and changed asregards the immediate illustration, all within the true intent and broadscope of the invention, as hereinafter defined and claimed.

Fig. l in the drawing is a plan view of one of the arresters shownconnected with tape or ribbon form of wiring, the tape and the groundconnection being indicated broken away.

Fig. 2 is a cross-sectional view taken along line 2-2 of Fig. 1.

Fig. 3 is a broken sectional view on substantially the plane of line 3-3of Fig. 1.

Fig. 4 is an enlarged broken sectional detail of one of the pointedcontact plates.

Fig. 5 is a plan view similar to Fig. 1, on smaller scale, showing theinvention connected with open twin wiring such as used with U. H. F. orV. H. F.

Fig. 6 is a broken sectional detail on substantially the plane of line66 of Fig. 5, on a larger scale.

Fig. 7 is a broken cross-sectional view showing the arrester mounted onand connected with a ground pipe.

In the embodiment illustrated, the base 10, of insulating material, maybe small enough and light enough to be supported on the wires and it isshown as having a wide V-groove 11 across the bottom of the same,enabling it to be centered and secured as shown in Fig. 7, over agrounding pipe 12.

The top of the base is shown as having a flat, shallow channel 13extending across the face of the same, wide and deep enough to contain abalanced two-conductor transmission line such as the television leadinribbon 14 as indicated in Figs. 1, 2, 3 and 7.

Also provided in the top of the base are the more widely spaced parallelgrooves 15, located at opposite sides of the central groove, and spacedwide enough apart to receive the conductors 16, Figs. 5 and 6, of theopen twin leadin wires.

A single set or pair of H-shaped centrally apertured terminal or bindingplates is used, holding either the ribbon or the open twin form ofconductors.

These H-shaped clamping or binding plates are designated 17 and they areshown in Fig. 1 with the transverse bar of each H seated in atransversely extending groove 18 in the top of the base, at oppositesides of the central longitudinal groove 13, and as havinglongitudinally extending lugs or fingers 19 formed by one leg of each Hat their inner edges, entered in the center groove 13 and similarlongitudinally extended fingers or lugs 20 at their outer edges, formedby the other leg of each H entered in the outer longitudinal grooves 15.

Additionally, these H-shaped terminal plates are shown as havingdownwardly struck, separately pointed, integrally formed insulationpiercing contact points 21 along their inner edges, approximately inline with the stranded conductors 22 of the ribbon.

It will be noted in Fig. 1 that the points 21 in each plate are arrangedin an arcuate line having a curvature sufiicient to take inthe Width ofa stranded conductor, thus to insure that one or more points will makecontact with the strands of the conductor.

Fig. 4 shows how the points 21 are forged out of the metal of the platein hollow, rounded, separately pointed cones which will pierce theinsulation 23 of the ribbon and force their way between the strands ofthe conductor, displacing the material in each case, rather than cuttingor tearing the same.

These are very important advantages assuring firm, positive contactwithout cutting or injuring the fine wire strands and without opening upor destroying the insulation.

The contact plates are adjustably secured on the base in theillustration by screws 24 extended through the back of the base, Fig. 2,and secured by nuts 25 at the front of the base, these screws continuedthrough openings provided in the plates and carrying the binding nuts 26which can be turned down to clamp the plates firmly engaged with theconductors.

A pair of spark gap plate members 27 are disposed in a recess within theinsulating body 10. The spark gap plate members 27 are symmetricallyarranged with respect to the longitudinal axis of an elongated groundedmember illustratively shown as a grounding screw 28 and comprise flatsurfaces which are coplanar with respect to a plane normal to thelongitudinal axis of grounding screw 28.

Each spark gap member 27 comprises an end portion which is disposed inproximity to and spaced from the grounding screw 23 to define a sparkgap from each spark gap member 27 to the common grounding screw 28.

An annular leakage member exemplified by a washer 29 formed ofhigh-resistance material such as carbon surrounds the grounding screw28. The carbon washer 29 has a fiat circular surface which is arrangedwith symmetrically disposed portions thereof in simultaneouselectrically conductive engagement with both of the two coplanarsurfaces of the spark gap member 27.

Fastening means are provided such as an electrically conductive nut 30threaded on the shank of grounding screw 28 which engages a metal Washer31. The metal washer 31 in turn presses against the high-resistanceannular carbon washer 29. The nut 30 and metal washer 31 engage asurface portion of carbon washer 29 remote from its opposite flatcircular surface which symmetrically engages the coplanar surfaces ofspark gap plate members 27. This provides symmetrical leakageconnections to grounding screw 28 through different portions of thecarbon washer 29 for each of the spark gap plates 27, each leakageconnection being individually shunted by one of the spark gaps.

The spark gap plate members 27 are secured to the insulating body by theheaded inner ends of terminal screws 24 and are thus connected to bothconductors of a two-wire transmission line through the H-shaped terminalplates 17.

In Figs. 1, 2 and 3 the ground connection is shown as provided by agrounding strip 32 engaged on screw 28 beneath the nut 30, this stripcarrying a binding screw 33 for a ground wire 34.

The grounding strip 32 is shown as extended from the screw 28 throughthe side of the base by way of a slot 35 and it will be noted in Figs. 2and 7 that aligned apertures or slots 35 are provided in both sides ofthe base so that a grounding strip or strips may be brought out ateither or both sides and so that, when required, a grounding clamp strip36 may be looped through the base and about a ground pipe 12, or othersuch support, and have its ends secured together by a screw 37, or thelike. This grounding clamp, as shown in Fig. 7 in engaged over the screw28 at the center and held between nut 30 and metal washer 31 so as toform a complete grounding connection.

Fig. 1 shows how, in addition to the possibility of supporting thearrester on the wires, or mounting it on a ground pipe, the device maybe mounted on a wall, or the like, by passing screws 38 through mountinglugs 39 extended from diagonally opposite corners of the base.

The lugs 19 and 20 extended from the inner and outer edges of the clampplates, securely grip and hold the conductors, both in the ribbon and inthe open twin forms of wiring, providing adequate strain relief.

The resister washer, in addition to providing a gap for lightningdischarge, also serves to dissipate static charges providing furtherprotection for the television set.

What is claimed is:

1. A lightning arrester of the class described, comprising a body ofinsulating material; an elongated electrically conductive centrallydisposed grounding member carried by said body; a pair of electricallyconductive flat-surfaced spark gap members carried by said body andsymmetrically arranged with respect to the longitudinal axis of saidgrounding member, said flat surfaces being substantially coplanar withrespect to a plane normal to the longitudinal axis of said groundingmember, each of said spark gap members comprising an end portiondisposed in proximity to and spaced from said grounding member fordefining a spark gap thereto; an annular leakage member formed ofhigh-resistance material surrounding said grounding member coaxiallytherewith, said leakage member having a circular flat surface withsymmetrically disposed portions thereof in simultaneous electricallyconductive engagement with both of said coplanar surfaces; electricallyconductive fastening means carried by said grounding member, saidfastening means electrically connecting said grounding member with aportion of said leakage member remote from said flat surfacesymmetrically with respect to said coplanar surface engaging portionsthereof and maintaining said portions of said flat surface in saidengagement with said coplanar surfaces; first terminal means carried bysaid body and electrically connected to said grounding member forconnecting said grounding member to ground; and second terminal meanscarried by said body and electrically connected to both of said sparkgap members, said second terminal means being adapted to connect bothconductors of a balanced two-wire transmission line symmetrically toground simultaneously through different portions of said leakage member,each of said different portions being individually shunted by one ofsaid spark gaps.

2. An arrester according to claim 1, in which said grounding member is ascrew having a threaded shank portion upon which said annular leakagemember is slidably mounted and wherein said fastening means comprises anelectrically conductive washer slidably mounted on said shank portionand engaging said leakage member, said fastening means furthercomprising an electrically conductive nut threaded on said shank portionand pressing said washer into engagement with said leakage member.

3. An arrester according to claim 2, wherein said body has a recessedback adapted to be mounted against a flat supporting surface, said nutand said Washer being mounted in said recess, and in which said body hasopposed aligned lateral apertures formed therein communicating with saidrecess and affording access to said grounding member, said firstterminal means comprising an elongated metallic ground strip adapted toextend around and secure said arrester to a ground pipe, said groundstrip extending through both of said apertures and through said recess,the portion in said recess extending between said nut and said washerfor combined electrical and mechanical connection to said groundingmember.

4. In combination with an insulating body having two spaced parallelgrooves formed therein and a transverseextending groove interconnectingsaid parallel grooves, the provision of a threaded binding post disposedin said transverse groove intermediate said parallel grooves andextending in a direction normal to the plane of said parallel grooves; acentrally apertured H- shaped terminal plate mounted on said bindingpost with said binding post extending freely slidably through saidaperture, each of the parallel legs of said H-shaped plate beingdisposed in one of said parallel grooves and extending inoppositedirections beyond said transverse groove, the transverse bar of saidH-shaped plate being disposed in said transverse groove; and a nutthreaded on said binding post and engageable With said plate forpressing a leg of said H-shaped plate into electrically conductivemechanical gripping engagement with a conductor disposed in either ofsaid parallel grooves.

5. The combination according to claim 4, further comprising an arcuaterow of integrally formed hollow, conical insulation piercing contactpoints extending 1ongitudinally along one of the parallel legs of saidH-shaped plate, said row of points being adapted to pierce theinsulation of an insulated conductor disposed in one of said parallelgrooves and establish positive electrical contact with the conductorportion thereof which is enclosed within said insulation.

References Cited in the file of this patent UNITED STATES PATENTS BrachApr. 1, 1930 Everett Jan. 22, 1935 Walter June 21, 1938 Wallace Nov. 4,1947 Johnson May 4, 1948 Reder June 14, 1949 Finkel Oct. 6, 1953Klostermann Jan. 19, 1954

